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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___CXX03___RANDOM_GEOMETRIC_DISTRIBUTION_H10#define _LIBCPP___CXX03___RANDOM_GEOMETRIC_DISTRIBUTION_H11 12#include <__cxx03/__config>13#include <__cxx03/__random/is_valid.h>14#include <__cxx03/__random/negative_binomial_distribution.h>15#include <__cxx03/iosfwd>16#include <__cxx03/limits>17 18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)19# pragma GCC system_header20#endif21 22_LIBCPP_PUSH_MACROS23#include <__cxx03/__undef_macros>24 25_LIBCPP_BEGIN_NAMESPACE_STD26 27template <class _IntType = int>28class _LIBCPP_TEMPLATE_VIS geometric_distribution {29 static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");30 31public:32 // types33 typedef _IntType result_type;34 35 class _LIBCPP_TEMPLATE_VIS param_type {36 double __p_;37 38 public:39 typedef geometric_distribution distribution_type;40 41 _LIBCPP_HIDE_FROM_ABI explicit param_type(double __p = 0.5) : __p_(__p) {}42 43 _LIBCPP_HIDE_FROM_ABI double p() const { return __p_; }44 45 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {46 return __x.__p_ == __y.__p_;47 }48 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }49 };50 51private:52 param_type __p_;53 54public:55 // constructors and reset functions56 _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(double __p = 0.5) : __p_(__p) {}57 _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(const param_type& __p) : __p_(__p) {}58 _LIBCPP_HIDE_FROM_ABI void reset() {}59 60 // generating functions61 template <class _URNG>62 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {63 return (*this)(__g, __p_);64 }65 template <class _URNG>66 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {67 return negative_binomial_distribution<result_type>(1, __p.p())(__g);68 }69 70 // property functions71 _LIBCPP_HIDE_FROM_ABI double p() const { return __p_.p(); }72 73 _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }74 _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }75 76 _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }77 _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::max(); }78 79 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const geometric_distribution& __x, const geometric_distribution& __y) {80 return __x.__p_ == __y.__p_;81 }82 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const geometric_distribution& __x, const geometric_distribution& __y) {83 return !(__x == __y);84 }85};86 87template <class _CharT, class _Traits, class _IntType>88_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&89operator<<(basic_ostream<_CharT, _Traits>& __os, const geometric_distribution<_IntType>& __x) {90 __save_flags<_CharT, _Traits> __lx(__os);91 typedef basic_ostream<_CharT, _Traits> _OStream;92 __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);93 return __os << __x.p();94}95 96template <class _CharT, class _Traits, class _IntType>97_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&98operator>>(basic_istream<_CharT, _Traits>& __is, geometric_distribution<_IntType>& __x) {99 typedef geometric_distribution<_IntType> _Eng;100 typedef typename _Eng::param_type param_type;101 __save_flags<_CharT, _Traits> __lx(__is);102 typedef basic_istream<_CharT, _Traits> _Istream;103 __is.flags(_Istream::dec | _Istream::skipws);104 double __p;105 __is >> __p;106 if (!__is.fail())107 __x.param(param_type(__p));108 return __is;109}110 111_LIBCPP_END_NAMESPACE_STD112 113_LIBCPP_POP_MACROS114 115#endif // _LIBCPP___CXX03___RANDOM_GEOMETRIC_DISTRIBUTION_H116